Fourteen months after post-Sept. 11 security worries drove MacDonald and dozens of other clam diggers off the flats near Logan International Airport, he returned Friday to the backbreaking work he loves.

Under a state law approved this summer, about 40 to 50 clam diggers who used to work the flats have been allowed to return - after being fingerprinted by police, issued new identification cards, and receiving their own security briefing.

MacDonald, 71, was among more than two dozen clammers who showed up Friday, their first day back.

"This is a godsend here, because Christmas is coming," MacDonald said.

The day after the terrorist attacks, clammers were evicted from about five miles of prime flats in Boston Harbor.

Massachusetts Port Authority officials then established a 500-foot security zone around the airport that included the rich clamming grounds.

The clammers appealed to lawmakers, who passed a law giving the diggers an exemption to the security zone, provided they passed background checks.

Massport officials frowned at the exemption, calling it a "less than ideal scenario in terms of securing the airport perimeter."

The clammers each have to pay $110 for the background check, fingerprinting and an ID card. They have to attend an anti-terrorism class, where they are told to immediately report any suspicious activity or people on the waters around Logan.

They also must wear a black and yellow vest while clamming in the secure zone.

The clammers are so familiar with the airport's noise and smell of burnt rubber, most knew something was amiss the morning of Sept. 11 when suddenly everything went silent.

It was only hours later that they learned two of the planes that left Logan that morning were hijacked and flown into the World Trade Center.

MacDonald said the clammers will make the airport more secure, not less.